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Kepler-78b is a planet that shouldn’t exist. This scorching lava world circles its star every eight and a half hours at a distance of less than one million miles — one of the tightest known orbits. According to current theories of planet formation, it couldn’t have formed so close to its star, nor could it have moved there.

Kepler-78b is a planet that shouldn’t exist. This scorching lava world, shown here in an artist’s conception, circles its star every eight and a half hours at a distance of less than one million miles. According to current theories of planet formation, it couldn’t have formed so close to its star, nor could it have moved there. (Credit: David A. Aguilar (CfA))

“This planet is a complete mystery,” says astronomer David Latham of the Harvard-Smithsonian Center for Astrophysics (CfA). “We don’t know how it formed or how it got to where it is today. What we do know is that it’s not going to last forever.”

“Kepler-78b is going to end up in the star very soon, astronomically speaking,” agrees CfA astronomer Dimitar Sasselov.

Not only is Kepler-78b a mystery world, it is the first known Earth-sized planet with an Earth-like density. Kepler-78b is about 20 percent larger than Earth, with a diameter of 9,200 miles, and weighs almost twice as much. As a result it has a density similar to Earth’s, which suggests an Earth-like composition of iron and rock.

Sep. 9, 2013 — NASA’s black-hole-hunter spacecraft, the Nuclear Spectroscopic Telescope Array, or NuSTAR, has “bagged” its first 10 supermassive black holes. The mission, which has a mast the length of a school bus, is the first telescope capable of focusing the highest-energy X-ray light into detailed pictures.

The new black-hole finds are the first of hundreds expected from the mission over the next two years. These gargantuan structures — black holes surrounded by thick disks of gas — lie at the hearts of distant galaxies between 0.3 and 11.4 billion light-years from Earth.

“We found the black holes serendipitously,” explained David Alexander, a NuSTAR team member based in the Department of Physics at Durham University in England and lead author of a new study appearing Aug. 20 in The Astrophysical Journal. “We were looking at known targets and spotted the black holes in the background of the images.”

Additional serendipitous finds such as these are expected for the mission. Along with the mission’s more targeted surveys of selected patches of sky, the NuSTAR team plans to comb through hundreds of images taken by the telescope with the goal of finding black holes caught in the background.

Aug. 29, 2013 — Astronomers using NASA’s Chandra X-ray Observatory have taken a major step in explaining why material around the giant black hole at the center of the Milky Way Galaxy is extraordinarily faint in X-rays. This discovery holds important implications for understanding black holes.

New Chandra images of Sagittarius A* (Sgr A*), which is located about 26,000 light-years from Earth, indicate that less than 1 percent of the gas initially within Sgr A*’s gravitational grasp ever reaches the point of no return, also called the event horizon. Instead, much of the gas is ejected before it gets near the event horizon and has a chance to brighten, leading to feeble X-ray emissions.

These new findings are the result of one of the longest observation campaigns ever performed with Chandra. The spacecraft collected five weeks’ worth of data on Sgr A* in 2012. The researchers used this observation period to capture unusually detailed and sensitive X-ray images and energy signatures of super-heated gas swirling around Sgr A*, whose mass is about 4 million times that of the sun.

This image of the moon was generated by data collected by NASA’s Moon Mineralogy Mapper on the Indian Space Research Organization’s Chandrayaan-1 mission. It is a three-color composite of reflected near-infrared radiation from the sun, and illustrates the extent to which different materials are mapped across the side of the moon that faces Earth. Image credit: ISRO/NASA/JPL-Caltech/Brown Univ./USGS› Full image and caption

August 28, 2013

PASADENA – NASA-funded lunar research has yielded evidence of water locked in mineral grains on the surface of the moon from an unknown source deep beneath the surface. Using data from NASA’s Moon Mineralogy Mapper (M3) instrument aboard the Indian Space Research Organization’s Chandrayaan-1 spacecraft, scientists remotely detected magmatic water, or water that originates from deep within the moon’s interior, on the surface of the moon.

The findings, published Aug. 25 in Nature Geoscience, represent the first detection of this form of water from lunar orbit. Earlier studies had shown the existence of magmatic water in lunar samples returned during NASA’s Apollo program.

M3 imaged the lunar impact crater Bullialdus, which lies near the lunar equator. Scientists were interested in studying this area because they could better quantify the amount of water inside the rocks due to the crater’s location and the type of rocks it held. The central peak of the crater is made up of a type of rock that forms deep within the lunar crust and mantle when magma is trapped underground.

Voyager 1 appears to have at long last left our solar system and entered interstellar space, says a University of Maryland-led team of researchers

Voyager 1 appears to have at long last left our solar system and entered interstellar space, says a University of Maryland-led team of researchers. (Credit: NASA)

Carrying Earthly greetings on a gold plated phonograph record and still-operational scientific instruments — including the Low Energy Charged Particle detector designed, built and overseen, in part, by UMD’s Space Physics Group — NASA’s Voyager 1 has traveled farther from Earth than any other human-made object. And now, these researchers say, it has begun the first exploration of our galaxy beyond the Sun’s influence.

“It’s a somewhat controversial view, but we think Voyager has finally left the Solar System, and is truly beginning its travels through the Milky Way,” says UMD research scientist Marc Swisdak, lead author of a new paper published online this week in The Astrophysical Journal Letters. Swisdak and fellow plasma physicists James F. Drake, also of the University of Maryland, and Merav Opher of Boston University have constructed a model of the outer edge of the Solar System that fits recent observations, both expected and unexpected.

Fourth of July is the perfect time to watch fiery masses streak across the sky. This speedy guy, the comet ISON, looks like it pretty much fits that bill. Except that it’s actually quite icy at its core, and it’s barreling toward the sun at around 48,000 miles per hour, faster than any firework.

This five-second loop of video is a compression of images taken by the Hubble Space Telescope over a period of 43 minutes in May, during which ISON covered 34,000 miles.